Glutaric AciduriaType 1: Clinical and Molecular Study in Iranian Patients, 3 Novel Mutations

Abstract

Objective Glutaricaciduria type 1 (GA1), is a rare, treatable neuro metabolic disease, due to glutaryl-CoA dehydrogenase (GCDH) gene mutation. In regions without neonatal blood screening (NBS), patients are diagnosed in symptomatic period. This study was carried out to assess patients with GA1 for clinical, biochemical, neuroimaging findings and GCDH gene mutations analysis. Materials & Methods In this cross-sectional study, clinical manifestation, neuroimaging and metabolic findings of eleven Iranian GA1 patients of MofidChildren's Hospital, Tehran, Iranbetween 2001 and 2011, were evaluated. Mutational analysis of the GCDH gene was performed on genomic DNA. Genomic DNA was extracted from peripheral lymphocytes using QIAamp DNA Micro Kit (Qiagen). All 11 exons and flanking intronic regions of the GCDH gene were amplified by polymerase chain reaction (PCR). Results All patients were diagnosed before 32 months old. Clinical presentations of GA1 include acute encephalopathic crisis and/or developmental delay and macrocephaly. Seven GCDH gene mutations were detected in our patients. The most frequent GCDH mutations occurred in exon7 then exon8, 10 and11. G244 C in exon7, R294 Q in exon8 and N373 S in exon 10 were three novel mutations. There was no correlation between of genotype and phenotype in our patients. Conclusion Physician must remember GA1 in differential diagnosis of acute encephalopathic crisis, macrocephaly, developmental delay, movement disorders such as dystonia and dyskinesia. Early detection, proper treatment and selective screening of patients' siblings can prevent neurologic disabilities.